Regulating device for powder nozzles



' Dec. 21, 1965 INVENTOR Guenie 7 Z BY M ATTORNEYS United States Patent3,224,748 REGULATING DEVICE FOR POWDER NOZZLES Giinter Biiddenhagen,Knapsack-Griesheim AG., Werk Griesheim-Antogen, Frankfurt am Main,Germany Filed Apr. 6, 1962, Ser. No. 185,636 Claims priority,application Germany, Apr. 12, 1961, K 43,446 3 Claims. (Cl. 26623) Thisinvention relates to an improved device for regulating powder nozzlesused for introducing a powdered auxiliary agent such as iron powder intothe stream of cutting oxygen employed in the flame scarfing of ingotsand like metal workpieces. More particularly, it concerns such a devicewhereby the width of the powder stream projected from the nozzle exit isconveniently regulated in accordance with the size of the workpiece tobe scarfed.

An improved powder nozzle for use in flame scarfing is disclosed in thecopending application Serial No. 130,- 131 filed August 8, 1961, byGiinter Biiddenhagen from which the powder is blown by means of aconveyor gas, preferably compressed air. Means are disposed within thepowder nozzle for distributing the powder uniformly over the width ofthe powder nozzle exit. A feature of the device there disclosed is thatthe powder is supplied to a location close to the nozzle exit solely bymeans of gravity before mingling with the stream of conveyor gas.

It is further disclosed in the copending application to provide thepowder nozzle with a regulating device for controlling the width of thepowder stream projected from the nozzle. Such regulation is achieved bycorrespondingly changing the width of the stream of conveyor gas flowingthrough the nozzle, preferably by means of a sliding valve disposed inthe channel through which the conveyor gas is supplied to the nozzleexit. It is obviously desirable for reasons of economy to project astream of powder no wider than the workpiece to be scarfed.

When employing a single powder nozzle in the scarfing machine with whichhowever only limited widths of workpiece can be scarfed, it isdisadvantageous that the regulating device of the copending applicationis difficultiy accessible and that the steering rod of the sliding valveprojects from the side of the device for a considerable distance whenthe valve is wide open. These disadvantages are particularly noticeablewhen the scarfing machine is to be employed for workpieces ofsubstantial width, for example for a scarfing width of 0.25 to 2 meters,in which case it is necessary to provide a plurality of powder nozzlesside by side. If in such case the width of the powder stream is to beregulated as disclosed in the copending application by means of a singlesliding valve arranged within the powder nozzles, this means that thegas channels across which the valve slides must be lined up preciselyand that no air spaces or gaps are permitted between the individualpowder nozzles. Furthermore, the steering rod of the sliding valve insuch case must have a length which corresponds at least to the maximumscarfing width and will extend in the case of a scarfing width of about2 meters out of side of the powder nozzle for some 2 meters when thevalve is wide open. It is also not possible to provide a remote controlwhen thus arranging the regulating device within the gas channel of thepowder nozzle.

In accordance with the present invention, it is therefore provided thatthe regulating device and the supply channel for the conveyor gas arearranged outside of the powder nozzle and that the supply channel isconnected to a plurality of channels in the nozzle by means of hoses,tubes, or the like. This has the advantage that r the regulating deviceand supply channel can be arranged independently of the powder nozzle ata suitable location where the steering rod of the sliding valve, whichprojects sideways, does not interfere. Furthermore, such location may bereadily accessible, and the heat which surrounds the powder nozzle needhave no detrimental effect. When arranging a plurality of powder nozzlesside by side, this has the further advantage that each powder nozzle maybe provided with a separate regulating device and-that the precisearrangement of the channels, the sealing of the nozzles with respect toeach other, and the very long steering rod of the sliding valve can beavoided. The regulating devices in such cases may be arranged at asingle or several desired locations either side by side, above andbelow, or before and behind each other.

As the regulating element there is preferably provided in the gas supplychannel a movable sliding valve, preferably a cylindrical piston. It ishowever also possible to employ closing valves in the hoses, tubes, orthe like, whereby the steering rod which projects sideways can beavoided, or other suitable regulating devices for the flow of a conveyorgas.

In a further embodiment of the invention the length of the gas supplychannel is made less than one-half the width of the powder nozzle.Generally for this purpose several channels are provided in the nozzlefor each connecting hose. In this fashion the regulating device can bemade substantially smaller, and the steering rod of the piston valve,when wide open, will not project so far from the side of the scarfingmachine. This is also the case if a single sliding valve is employed fora plurality of powder nozzles. For the purpose of bringing together theentire regulating device at a location removed from the scarfingmachine, for example at a control panel for the same, the smallness ofthe regulating device is of advantage, quite aside from the lessening ofthe amount of materials required.

In the apparatus according to the invention it is also possible by valvemeans connected in parallel to adjust the streams of scarfing oxygenand/or heating gas for the scarfing heads to any desired width.

The invention will be described in connection with a single embodimentshown in the accompanying drawing in which:

FIG. 1 is a sectional elevational view of a. powder nozzle and itsassociated regulating device; and

FIG. 2 is a sectional view along the line II--II in FIG. 1.

The powder nozzle 1 is provided with a plurality of channels 3 out ofwhich the powder is blown by a conveyor gas which in this case iscompressed air introduced through a pipe 8 into the channel 4 and fromthere through a plurality of flexible hoses 2 to the nozzle channels 3.In order to shorten the supply channel 4, three nozzle channels 3 areconnected to each hose 2. The powder is conveyed into the nozzle channel3 through a bore 7, as may be seen in FIG. 2.

The regulation of the width of the powder stream projected out of nozzlechannels 3 is accomplished by closing one or more of the hoses 2 fromthe supply channel 4, i.e. by sliding the piston valve 5. Since there isno compressed air available in the closed-off nozzle channels 3, nopowder can blow out of them.

The steering rod 6 of the piston valve 5, due to the shortening of thesupply channel 4, hardly projects beyond the powder nozzle 1 and isprovided with a scale on which the width of the powder stream may beread.

While the invention has been described in connection with a specificembodiment, other modifications thereof will be apparent to thoseskilled in this art without departing from the spirit and scope of theinvention which is defined in the appended claims.

What is claimed is:

1. An apparatus for flame scarfing metallic workpieces comprising incombination a powder nozzle having a plu-v rality of sets of outletchannels spaced over a pre-determined width dimension, each setincluding at least two outlet channels and a common inlet channel,powder feed means connected to each outlet channel in said sets forfeeding powder thereto,.pressure means connected to each of said inletchannels to accelerate the flow of powder through said outlet channels,:said pressure means including pressure medium supply connecting means,a manifold communicating with said pressure medium supply connectingmeans, said manifold being spaced from said nozzle and having a widthsubstantially smaller than said predetermined nozzle Width dimension, aplurality of conduits connected to said manifold, each of said conduitscommunicating with a respective inlet channel of said sets of saidoutlet channels, and sliding valve means in said manifold for closing aselected number of said conduits and their respective sets of outletchannels in accordance with the extent to which said valve means isinserted-into and extended out of said manifold.

2. An apparatus as set forth in claim 1 wherein said valve means is apiston valve having an elongated rod connected thereto extending fromone end of said manifold, the other end of said manifold communicatingwith said pressure medium supply means and the overall Width of saidmanifold and said piston rod in its fully extended position being nogreater than said pre-determined nozzle width.

3. An apparatus as set forth in claim 1 wherein each of said sets ofoutlet channels includes three outlet channels.

References Cited by the Examiner UNITED STATES PATENTS 2,451,422 10/1948Wagner 266-23 2,622,048 12/1952 Moesinger, 148-95 2,754,234 7/1956 Holubet al. 1489.5

FOREIGN PATENTS 484,684 7/1952 Canada. 251,091 4/ 1926 Great Britain.

WHITMORE A. WILTZ, Primary Examiner. MORRIS WOLK, Examiner.

1. AN APPARATUS FOR FLAME SCRAFING METALLIC WORKPIECES COMPRISING INCOMBINATION A POWDER NOZZLE HAVING A PLURALITY OF SETS OF OUTLETCHANNELS SPACED OVER A PRE-DETERMINED WIDTH DIMENSION, EACH SETINCLUDING AT LEAST TWO OUTLET CHANNELS AND A COMMON INLET CHANNEL, POWERFEED MEANS CONNECTED TO EACH OUTLET CHANNEL IN SAID SETS FOR FEEDINGPOWDER THERETO, PRESSURE MEANS CONNECTED TO EACH OF SAID INLET CHANNELSTO ACCELERATE THE FLOW OF POWDER THROUGH SAID OUTLET CHANNELS, SAIDPRESSURE MEANS INCLUDING PRESSURE MEDIUM SUPPLY CONNECTING MEANS, AMANIFOLD COMMUNICATING WITH SAID PRESSURE MEDIUM SUPPLY CONNECTINGMEANS, SAID MANIFOLD BEING SPACED FROM SAID NOZZLE AND HAVING A WIDTHSUBSTANTIALLY SMALLER THAN SAID PREDETERMINED NOZZLE WIDTH DIMENSION, APLURALITY OF CONDUITS CONNECTED TO SAID MANIFOLD, EACH OF SAID CONDUITSCOMMUNICATING WITH A RESPECTIVE INLET CHANNEL OF SAID SETS OF SAIDOUTLET CHANNELS, SAID SLIDING VALVE MEANS IN SAID MANIFOLD FOR CLOSING ASELECTED NUMBER OF SAID CONDUITS AND THEIR RESPECTIVE SETS OF OUTLETCHANNELS IN ACCORDANCE WITH THE EXTENT TO WHICH SAID VALVE MEANS ISINSERTED INTO AND EXTENDED OUT OF SAID MANIFOLD.